ex_data_table_step.relop_rename_columns {rqdatatable}

Rename columns.

Description

data.table based implementation.

Usage

## S3 method for class 'relop_rename_columns'
ex_data_table_step(
  optree,
  ...,
  tables = list(),
  source_usage = NULL,
  source_limit = NULL,
  env = parent.frame()
)

Arguments

optree

relop operations tree.

...

not used, force later arguments to bind by name.

tables

named list map from table names used in nodes to data.tables and data.frames.

source_usage

list mapping source table names to vectors of columns used.

source_limit

if not null limit all table sources to no more than this many rows (used for debugging).

env

environment to work in.

Examples

dL <- build_frame(
    "x", "y" |
    2L , "b" |
    1L , "a" |
    3L , "c" )
rquery_pipeline <- local_td(dL) %.>%
  rename_columns(., c("x" = "y", "y" = "x"))
dL %.>% rquery_pipeline